The findings are published online past times the Proceedings of the National Academy of Sciences.
The scientists examined sulfur bacteria, microorganisms that are equally good modest to come across amongst the unaided eye, that are 1.8 billion years onetime in addition to were preserved inwards rocks from Western Australia’s coastal waters. Using cutting-edge technology, they flora that the bacteria await the same equally bacteria of the same portion from 2.3 billion years agone — in addition to that both sets of ancient bacteria are indistinguishable from modern sulfur bacteria flora inwards mud off of the coast of Chile.
“It seems astounding that life has non evolved for to a greater extent than than two billion years — almost one-half the history of Earth,” said J. William Schopf, a UCLA professor of earth, planetary in addition to infinite sciences inwards the UCLA College who was the study’s Pb author. “Given that development is a fact, this lack of development needs to live explained.”
Charles Darwin’s writings on development focused much to a greater extent than on species that had changed over fourth dimension than on those that hadn’t. So how hit scientists explicate a species living for then long without evolving?
“The dominion of biological scientific discipline is non to evolve unless the physical or biological surroundings changes, which is consistent amongst Darwin,” said Schopf, who also is manager of UCLA’s Center for the Study of Evolution in addition to the Origin of Life. The surroundings inwards which these microorganisms alive has remained essentially unchanged for three billion years, he said.
“These microorganisms are well-adapted to their simple, really stable physical in addition to biological environment,” he said. “If they were inwards an surroundings that did non modify only they nonetheless evolved, that would bring shown that our agreement of Darwinian development was seriously flawed.”
Schopf said the findings thence render farther scientific proof for Darwin’s work. “It fits perfectly amongst his ideas,” he said.
The fossils Schopf analyzed appointment dorsum to a substantial ascent inwards Earth’s oxygen levels known equally the Great Oxidation Event, which scientists believe occurred betwixt 2.2 billion in addition to 2.4 billion years ago. The termination also produced a dramatic increase inwards sulfate in addition to nitrate — the alone nutrients the microorganisms would bring needed to last inwards their seawater mud surroundings — which the scientists state enabled the bacteria to thrive in addition to multiply.
Schopf used several techniques to analyze the fossils, including Raman spectroscopy — which enables scientists to await within rocks to create upwards one’s remove heed their composition in addition to chemical scientific discipline — in addition to confocal Light Amplification by Stimulated Emission of Radiation scanning microscopy — which renders fossils inwards 3-D. He pioneered the purpose of both techniques for analyzing microscopic fossils preserved within ancient rocks.